Percussion hammer



July l5, 1969 c. v. ADAMS PERCUSSION HAMMER 2 Sheets-Sheet l Filed July 3. 1967 FIG. I

INVENTOR:

CAMPBELL V ADAMS AT Ys July l5, 1969 c. v. ADAMS 3,455,208

PERCUSSION HAMMER Filed July 5, 1967 2 Sheets-Sheet 2 F|G.3 H64 W INVENTOR: CAMPBELL ADAMS ATT'YS United States Patent O 3,455,208 PERCUSSION HAMMER Campbell V. Adams, Chicago, Ill., assignor to Vulcan Iron Works Inc., Chattanooga, Tenn., a corporation of Illinois Filed July 3, 1967, Ser. No. 651,043 Int. Cl. F011 31/18 U.S. Cl. 91-352 9 Claims ABSTRACT OF THE DISCLOSURE There is provided a pile driving hammer including a cylinder, a piston operated in the cylinder, and a ram reciprocated by the piston. It is conventional in such hammers to provide valve mechanism for controlling the supply of motive fluid to the cylinder so as to cycle the piston and the associated ram. A slide bar connected to the ram is provided for controlling the valve mechanism. The pile driving hammer is provided with an improved pivotal connection between the ram and the slide bar.

The present invention relates to a percussion hammer particularly useful as a pile driving hammer but also applicable to other percussion hammer applications. One such known percussion hammer is described in my earlier Patent 2,004,180 granted June 11, 1935.

The hammer illustrated in my earlier patent is of the type including a cylinder, a piston operated within the cylinder, and a ram reciprocated by the piston for imparting impact blows to an anvil or pile head. A valve assembly is provided for controlling the supply of motive fluid to the cylinder in the desired manner to cycle the piston and the associated ram through its up and down strokes. A slide bar is connected to the ram for reciprocation therewith and controls the operation of the valve mechanism.

The means generally used commercially for securing the slide bar to the ram fastens the slide bar rigidly to the ram. This may be accomplished by passing a key through a slot in both the ram and the slide bar. The looseness of the ram on its guides while it is reciprocated requires that the slide bar, which is guided by a groove in the cylinder housing, have sufficient play provided in attachment to the ram to assure proper orientation with the guiding groove in the cylinder housing. Thus ample freedom of movement without binding is essential. However such commercial assembly has not been entirely satisfactory in this regard and has resulted in binding and failure of the members involved.

Accordingly one object of the present invention is to provide a new and improved percussion hammer which avoids the above mentioned diti'iculty.

Another object of the present invention is the provision of an improved means for securing the slide bar to the ram of a percussion hammer.

Yet another object of the present invention is to provide a new and improved percussion hammer.

Further objects and advantages of the present invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

The present invention is intended for use with a known type of percussion hammer particularly of the type used in driving piles, and including a cylinder housing defining .a cylinder and having a piston operated in the cylinder with a ram rcciprocated by the piston. Valve mechanism is provided for controlling the supply of motive uid to Patented July 15, 1969 ICC the cylinder to cycle the piston and the associated ram. A slide bar is connected to the ram for reciprocation therewith and controls the operation of the valve mechamsm.

In accordance with the present invention the slide bar is connected to the ram by a pivotal connection which will accommodate reasonable misalignment between the component parts. In a preferred embodiment the pivotal connection is formed by a ball and socket joint wherein the socket is defined within a gripper member, and the gripper member is secured to a ram by a key connection.

Thus the method of attaching the slide bar to the ram according to the present invention avoids all the restraints to universal movement of slide bars encountered in connection with present commercial methods of attachment While additionally providing a simple, easy means of assembly and the securement thereof in a hole provided in the ram by the utilization of a key or similar securing device.

For a better understanding of the present invention reference may be had to the accompanying drawings wherein:

FIG. 1 is an elevational vieW of a percussion hammer incorporating the present invention;

FIG. 2 is a detail cross sectional view of a slide and ram connection in the hammer of FIG. 1 in accordance with the present invention;

FIG. 3 is a side view of the slide and ram connection of FIG. 2; and

FIG. 4 is an exploded perspective view of the connecting components of the slide bar and ram.

Referring now to the drawings, there is illustrated a percussion hammer 10, FIG. l, having an improved slide bar to ram connection according to the present invention and including a cylinder housing 11 defining an internal cylinder 11a closed at its upper end by a cylinder head 13. A piston assembly 14 is provided including a piston 15 reciprocable within the cylinder 11a and including a piston rod 16 extending through the lower end of the cylinder 11a connected to a suitable ram 17 guided for reciprocal movement on a plurality of guides 18 and adapted to strike against an anvil or pile. The reciprocal movement of the piston 15 is under the control of a known valve mechanism 22 which controls the admission and exhaust of motive fluid into and out of the cylinder 11a. The valve mechanism 22 includes a valve element 23 which is adapted to be rocked by a trip 24 including a pair of trip elements 25 and 26. The trip 24 of the valve mechanism 22 is operated by a slide 30 guided within a slide groove 31 for reciprocal movement with the ram 17, and connected at its lower end to the ram 17. The slide 30 is provided with suitable cams 31 and 32 adapted to engage the trip elements 25 and 26, respectively, for rocking the valve element 23 in response to reciprocation of the ram 17 and associated piston 15. The structure thus far described is known and may, if desired, be similar to that described in my earlier patent mentioned above.

In accordance with the present invention there is provided a lpivotal or swivel connection between the slide bar 30 and the ram 17. Such connection in the illustrated drawings takes the form of a ball and socket joint between these members. More specifically, to this end, the ram 17 is provided with a bore 36 in its upper surface for receiving the lower end of the slide bar 30 and enlarged at its upper end as illustrated at 36a. A gripper plug assembly 40 is secured within the bore 36 by a suitable wedge key 41 driven through aligned slots 42, 43 in the ram 17 and the gripper plug assembly 40, respectively. The key 41 has a tapered lower surface 41a so that the gripper plug assembly 40 may be driven tight within the bore 36. A pin 44 inserted within a selected one of a plurality of holes 45 in the key 41 prevents accidental release of the key 41.

The gripper plug assembly 40 is provided with an upwardly opening chamber 48 (FIGS. 2 and 4) terminating in an inner enlargement 49 having upper and lower spherical surfaces S and 51, respectively. ln the illustrated embodiment of the present invention, the gripper plug assembly includes an outer housing split longitudinally into sections 40a and 40b to provide for insertion of the slide bar, and includes a removable lower end block 40C secured in the lower end of the chamber 48 to define the spherical surface 51 in its upper surface. The lower end of the slide -bar 30 is provided with a ball or enlargement 30a having an upper and lower spherical surface 54, 55, respectively, mating with the spherical surfaces S0 and 51 in the gripper plug assembly 40.

To provide lateral clearance between the slide bar 30 and the chamber 48, the upper portion of the chamber 48 is tapered upwardly and outwardly relative to the slide bar 30, as defined by angle a, FIG. 2, to provide pivotal clearance between the slide bar 30 and the sides of chamber 48. In the illustrated embodiment the slide bar 30 has a portion extending upwardly from the enlargement 30a thereof tapering upwardly and outwardly, and consequently the chamber 48 has an adjacent portion tapering upwardly and outwardly at the angle a greater than the taper on the portion of the slide bar.

From the foregoing description it will be understood that the slide bar may pivot or swivel in all directions relative to the ram. Therefore, there is avoided all the restraints encountered on the slide bar and ram in the present commercial methods of attachment. Additionally, the enlargement at the lower end of the slide bar is readily gripped within the gripper plug assembly 49 prior to its positioning within the bore 36 of the ram. Once the gripper bar assembly 40 is in place, the key 41 is driven through the cooperating slots 42, 43 and is thus secured Within the ram. The key 41 prevents the gripper plug assembly from rotating but permits rotational and oscillative movement of the slide bar 30 relative thereto.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. The improvement in a pile driving hammer of the type including a cylinder housing defining a cylinder, a piston operated in said cylinder, a ram reciprocated by said piston, valve means for controlling the supply of motive uid to said cylinder to cycle said piston and associated ram, and a rigid slide bar directly connected with said ram for longitudinal reciprocation therewith and for controlling the operation of the said Valve means, said improvement comprising a pivotal connection between said ram and said rigid slide bar.

2. The improvement as set forth in claim 1 including guide means defined in said cylinder housing for guiding said slide rigid bar.

3. The improvement in a pile driving hammer of the type including a cylinder housing defining a cylinder, a piston operated in said cylinder, a ram reciprocated by said piston, valve means for controlling the supply of motive iiuid to said cylinder to cycle said piston and associated ram, a slide bar connected for reciprocation with said ram controlling the operation of the said valve means, said improvement comprising a pivotal connection between said ram and said slide bar; said valve means including trip means, and said slide bar including cam means engageable with said trip means.

4. The improvement in a pile driving hammer of the type including a cylinder housing deiining a cylinder, a piston operated in said cylinder, a ram reciprocated by said piston, valve means for controlling the supply of motive fluid to said cylinder to cycle said piston and associated ram, a slide bar connected for reciprocation with said ram controlling the operation of the said valve means, said improvement comprising a pivotal connection between said ram and said slide bar; said ram including a bore for receiving the slide bar, and a gripper plug means within said bore and including an upwardly opening chamber terminating in an inner enlargement having upper and lower spherical surfaces, the lower end of said slide bar being provided with an enlargement having upper and lower spherical surfaces for engaging the first mentioned spherical surfaces.

5. The improvement as set forth in claim 4 wherein said chamber has an upper portion extending from said inner enlargement tapered upwardly and outwardly relative to said slide bar to provide pivotal clearance with said slide bar.

6. The improvement as set forth in claim 5 wherein the portion of the slide bar extending into said upper portion is tapered upwardly and outwardly, and said upper portion is provided with a greater upward and outward taper than said slide bar.

7. The improvement as set forth in claim 4 wherein the lower spherical surface of said chamber is deiined in a removable end block received in said gripper plug means to lock said slide bar in place.

8. The improvement as set forth in claim 4 wherein said gripper plug means is split longitudinally to provide for insertion of said enlargement on said slide bar.

9. The improvement as set forth in claim 4 wherein said gripper plug means and said ram are provided with transversely aligned slots, and wherein there is provided key means through said slots securing said gripper plug means to said ram.

References Cited UNITED STATES PATENTS 400,519 4/ 1889 Trethewey 91-350 470,723 3/ 1892 Trethewey 91-350 2,004,180 6/ 1935 Adams 91-352 2,429,780 10/ 1947 Terhune 9 1-3 52 PAUL E. MASLOVSKY, Primary Examiner U.S. Cl. X.R. 173-127 

